INS Arihant left crippled after ‘accident’ 10 months ago

Indigenous nuclear submarine INS Arihant suffered major damage because of possible human error and has not sailed now for months, according to Navy sources. Arihant is the most important platform within India’s nuclear triad covering land-air-sea modes.

Arihant’s propulsion compartment suffered damage after water entered the area more than 10 months ago, according to details available with The Hindu. One naval source said water rushed in because a hatch on the rear side was left open by mistake. The Ministry of Defence did not respond to questions from The Hindu.

The accident

The indigenous nuclear submarine, built under the Advanced Technology Vessel project (ATV), suffered damage while it was at harbour. Since the accident, the submarine has been undergoing repairs and clean up, and has not sailed, sources said.

Besides other repair work, many pipes had to be cut open and replaced. One naval source said the “cleaning up” is a laborious task in a nuclear submarine which is why there has been a delay in getting it back to sea.

Arihant’s issue has arisen soon after INS Chakra, the nuclear submarine leased from Russia, was reported to have suffered damage to its sonar domes while entering the harbour in Visakhapatnam in early October. However, INS Chakrahas only a peripheral role in the nuclear triad, for both training and escorting, since it is INS Arihant that would carry nuclear missiles.

The absence of Arihant from operations came to the political leadership’s attention during the India-China military stand-off at Doklam. Whenever such a stand-off takes place, countries carry out precautionary advance deployment of submarine assets. INS Arihant (Code name S2) came into the limelight on July 26, 2009, the day Gursharan Kaur, wife of Prime Minister Manmohan Singh, broke the auspicious coconut to launch India’s first nuclear-powered ballistic missile submarine in Visakhapatnam.

After that, the submarine was towed to an enclosed pier for extensive harbour trials from the dry docks at Ship Building Centre, away from public view. INS Arihant was quietly commissioned into service in August 2016 and its induction is still not officially acknowledged. It is powered by an 83 MW pressurised light-water reactor with enriched uranium.

Senior naval sources maintain that INS Arihant has not left the harbour for the last ten months or so, and has faced problems from the start. Initial delays could be just teething trouble, glitches at various stages of getting the reactor to go critical and during harbour trials; major differences between the Russian-supplied design and indigenous fabrication are said to have left many issues unaddressed satisfactorily.

Arihant: top gun for second-strike

INS Arihant, India’s only operational ship submersible ballistic nuclear (SSBN) asset, is its most dependable platform for a second-strike, given the country “no first use” on nuclear weapons. The other options, land-based and air-launched, are easier to detect.

The submarine is manned by a staff of 100 with extensive training from the School for Advanced Underwater Warfare in Visakhapatnam and further hands-on training on INS Chakra, a Nerpa-class nuclear ship.

Arihant has been immobilised even as the second ballistic missile submarine, Arighat, was launched on November 19 for sea trials. The launch was kept a low-profile event attended by Defence Minister Nirmala Sitharaman and senior Navy officers.

A high-profile launch, to be attended by the Prime Minister, was put off.

Key to nuclear triad

INS Arihant and other nuclear launch platforms — land-based missiles and designated aircraft — are operationally handled by the Strategic Forces Command, and report to the Nuclear Command Authority chaired by the Prime Minister.

However, the over 100 nuclear warheads are not mated with missiles or bombs and remain in civilian custody of the Atomic Energy Department and the Defence Research and Development Organisation.

Ambitious plan

India has an ambitious plan to build a SSBN fleet, comprising five Arihant-class vessels.

Naval sources say the plan hinges on Arihant’s success. It has taken 30 years to build it, at a high cost. “It was initially estimated to cost about ?3000 crore for three boats — now the cost of Arihant itself seems to have gone over ?14,000 crore,” a former high-ranking naval officer said.

The Eastern Naval Command plans to operate its nuclear sub fleet from an independent Naval Operational Alternative Base (NOAB) being constructed on 5,000 acres of land at Rambilli, for direct access to the sea. The base is located about 50 km from Visakhapatnam, and jetties are under construction.